US12043976B2 - Masonry block - Google Patents

Abstract

A method of forming simulated stone or brick column or a retaining wall is made up of rows of masonry blocks of generally trapezoidal configuration arranged in end-to-end relation to one another in each row, each block including a recessed portion being aligned with one another in each row and each block having textured wall surfaces simulating the appearance of brick or stone along one or more wall surfaces arranged in different configurations without the necessity of interlocking the blocks together.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of allowed U.S. Ser. No. 15/699,907, filed Sep. 8, 2017 titled METHOD OF MAKING MOLDED CONCRETE BLOCKS HAVING SIMULATED BRICK OR STONE OUTER SURFACES, which is a divisional of U.S. Ser. No. 14/176,991 (now U.S. Pat. No. 9,758,943), filed Feb. 10, 2014 titled MOLDED CONCRETE BLOCKS HAVING SIMULATED BRICK OR STONE OUTER SURFACES AND METHOD OF MAKING SAME, which claims priority to, and the benefit of, U.S. Provisional Application No. 61/762,685 filed Feb. 8, 2013 for COMPOSITE MOLDED CONCRETE BLOCKS HAVING TEXTURED FRONT SURFACES DEFINING SIMULATED BRICK OR STONE AND MORTAR CLUSTERS AND METHOD OF MAKING SAME all of which are incorporated by reference herein.

BACKGROUND AND FIELD

There is a need for concrete or masonry blocks which can be molded with different textured surfaces and combined to form retaining walls of different sizes and configurations in a simplified, efficient manner. In this regard, it is highly desirable to form each block in a mold which is positioned to provide a textured finished face for each block in a front vertical wall of the mold, and the remainder of the side and end wall surfaces of the mold inclining downwardly and inwardly to result in the formation of downwardly tapered side and rear walls in the resultant block in order to facilitate removal of the block from the mold. In order to further expedite removal of each block, a hinge is provided in opposite sides or along the bottom of each mold together with placement of cavities in the bottom and rear walls of each block in a manner to be described. One or more molds may be placed on a production board, the molds preferably being formed of a rubber or rubber-like material, and the blocks are formed by a wetcast process followed by curing and separation from each mold. In particular, the concrete block is of generally trapezoidal configuration with a front textured surface which takes on the appearance of a brick, stone and mortar cluster, different stone or rock-like textures. Each block is characterized also by having a rear wall and sidewalls joined together into a trapezoidal configuration, and the blocks can be arranged in various configurations, such as, for example, straight, rectangular, circular or serpentine walls without the necessity of inter-locking or otherwise physically joining the blocks together.

When used for retaining walls, a typical block is dimensioned to be 16″ wide by 6″ high at thefront wall surface12 and 8″ to 9″ in depth from thefront surface12 to therear surface14 depending upon the depth of the texture and the slope at the rear of theblock10 and will weigh in the order of thirty to fifty pounds each, although dimensions and weights may vary without departing from the scope. If necessary, the blocks can be joined by the application of construction adhesive between layers of block to prevent shifting in relation to each other. For taller retaining walls the blocks can also be anchored into the earth fill behind the wall by the use of a geogrid material that will extend between upper and lower layers of blocks. In addition, rods may be placed under each geogrid and within the void on the underside of each block and further anchored by the use of the elongated rods positioned against the geogrid in each void and locked in place by means of friction or pinch points between each rod and void. Both the geogrid and rod for each layer will extend continuously in a lengthwise direction beneath each row of blocks although these may be alternated as well. Also, the rods should be flexible enough to permit shaping of the entire wall into different configurations.

There is provided a method for molding a concrete block comprising the steps of: providing an outer rigid form having upstanding front and rear walls and opposite end walls arranged in a generally rectangular configuration; an elastomeric insert having a generally rectangular cavity defining front and rear wall surfaces and opposite end surfaces removably inserted into the form, at least one of the front, rear and end wall surfaces having a desired texture simulating a brick or stone to a block to be cast in said cavity; providing an upper opening into the cavity and filling the cavity with a wet cast colored concrete; vibrating the mold to densify and level out the concrete in the mold; curing the concrete in the mold over a predetermined time interval to form a hardened block of concrete; and removing the block from the mold.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG.1 is a front perspective view of one form of concrete block illustrating placement of a geogrid and rod into a void in the undersurface of each block in accordance with one aspect;

FIG.2 is a top plan view ofFIG.1;

FIG.3 is a cross sectional view taken about lines3-3 ofFIG.2;

FIG.4 is a rear view ofFIG.1;

FIG.5 is a perspective view of a retaining wall comprised of a number of composite blocks having different textured frontal surfaces and end surfaces;

FIG.6 is a perspective view of a production board having a plurality of support frames with a mold inserted in one of the support frames;

FIG.7 is a perspective view of a preferred form of mold including a V-shaped slot at each end of the mold adjacent to its front wall;

FIG.8 is a side view of a mold filled with concrete beneath a vacuum tool;

FIG.9 is an exploded view of the mold shown inFIG.8 with the cured block being removed with the aid of the vacuum tool;

FIG.10 is a perspective view of a modified form of mold having textured surfaces along the front and end of the interior of the mold;

FIG.11 is a perspective view of the resultant block formed in the mold ofFIG.10; and

FIG.12 is a top plan view of a retaining wall in a serpentine form.

DETAILED DESCRIPTION OF EMBODIMENTS

Referring in detail to the drawings, a composite concrete ormasonry block10 is illustrated inFIGS.1-3 and comprises a fronttextured wall surface12 and arear wall surface14, which is tapered downwardly from a tophorizontal surface16. Similarly,opposite sidewalls17 and18 are generally rectangular or trapezoidal in shape and taper downwardly from thetop surface16, and along with the front andrear surfaces12 and14 terminate in a bottomhorizontal surface20 which is parallel to thetop surface16. It will be evident by virtue of the downwardly taperedrear surface14 andsidewall surfaces17 and18 which terminate in adjoining relation to thebottom surface20 that the area or size of the bottom surface is less than the area of the top surface. Nevertheless, by virtue of the perpendicular relationship between thefront surface12 and thebottom surface20, the frontal surface is upstanding or vertical when thebottom surface20 is resting upon a horizontal surface, such as, level ground or on the level top surface of a lower adjoining block of a retaining wall as will be hereinafter described.

Preferably, therear surface14 is formed with acavity22 and the bottom surface is formed with acavity24 that extends the length of thebottom surface20 to reduce the weight of each block and facilitate gripping of the rear surface to remove from the mold and for carrying purposes.

For the purpose of illustration but not limitation,FIGS.4 and5 illustrate the utilization ofconcrete blocks10 of the present invention in the construction of aretaining wall30. Typically, the finished dimension of eachblock10 may be on the order of 16″ wide by 6″ high at thefront wall surface12 and 8″ to 9″ in depth from thefront surface12 to therear surface14 depending upon the depth of the texture and the slope at the rear of theblock10. Again, the voids orcavities22 and24 in each block on therear surface14 andbottom surface20 serve to reduce the overall weight of eachblock10 by reducing the amount of material required without reducing the overall dimensions of each block. Also, thecavity22 serves as a lifting handle to assist in lifting the retaining wall block from the mold without disturbing the overall dimensions of the block, along with the use of a vacuum to hold the stone while the mold is being removed by hand. The mold may also be removed manually by turning the mold over and allowing the block to be removed by gravity pull.

In the retaining wall structure illustrated inFIG.5, like blocks are correspondingly enumerated. Thus, the lower course ofblocks32,10,34,35 and36 are placed on a level surface either above or below ground level to establish a firm footing for the retaining wall. The next course consisting ofblocks38,36,10, and35 may be placed directly on thetop surfaces20 of the first course and an upper course comprisesblocks10,35,36 and38. When erected along a straight or curved line the upper front chamfered vertical edges of the adjoining or adjacent blocks are positioned flush with one another with a slight gap between facing sidewalls as a result of the tapered configuration of the sidewalls as described earlier. Blocks can be joined by use of construction adhesives between the layers to prevent movement in relation to one another. Of course, if the retaining wall is curved to any degree or serpentine as shown inFIG.12, the upper edges and adjoining edges will not be completely flush with one another but the chamfered front vertical corners and the wedge shape of the block itself allows for easy configuration of the curved wall.

Variations of texture as illustrated inFIGS.4 and5 will be hereinafter discussed in greater detail in connection with the method of manufacture, and the same is true of the composition of the concrete and additives utilized to control the characteristics of the concrete all in accordance with well-known practice. Thus, any variety of concrete mixture can be used depending upon the desired strength, color and other characteristics to be incorporated into the blocks.

Molds and Method of Manufacturing Blocks

As illustrated inFIGS.6-8, the concrete blocks are formed by introduction of a concrete mixture consisting of aggregate sand, cement, water, and water-reducing admixtures, with or without iron oxide color. The minimum strength of the concrete is on the order of 4,000 psi. Eachmold50 is preferably of a rubber or rubber-like composition having acentral cavity51 of generally trapezoidal configuration defined by aback wall52,opposite sides53,54 and a fronttextured wall55, the walls52-54 being tapered on both sides to facilitate ease of removal of the hardened concrete from the rubber mold as well as from a production board B. In turn,front wall55 has an inner face of a stone texture which is duplicated from natural stone. The stone texture is transferred to the mold using a multi-step process combining natural stone, liquid rubber or any liquefied material that will harden to duplicate the texture formed by rubber. A raisedportion58 in the bottom wall of the mold is of elongated triangular configuration and is shaped to form the void orcavity24 extending from end-to-end in each block; and a raisedportion60 in therear wall52 is of elongated generally triangular configuration and results in thecavity22 in the rear surface of each block.

In a preferred method of manufacture, one ormore rubber molds50 are placed on a standard production board B which can be of various sizes depending upon the manner in which concrete is placed in each mold. For eachrubber mold50, in order to maintain the desired shape, one well-known procedure is to utilize a BFS SlabFlex® machine. Any other type of machinery that produces wet cast products may be used as well. Any mold configuration of one or more molds can be mounted on a board B or platform prior to placing concrete in the molds. The molds are positioned so that the texturedfront wall surface56 is in a vertical position.Support frames46 are anchored byscrews48 on the production board B in surrounding relation to the mold during concrete placement. Theframes46 are tight enough to prevent thevertical keyways62 cut in the mold from opening and allowing concrete to leak through the cuts as hereinafter described in more detail.

Preliminary to placement of the concrete in each mold, a form release agent is applied to the interior of the mold to prevent the concrete from sticking to the mold and prevent bugholes from occurring. Preferably, a water-based release agent is used. The inner front wall surface of each mold is surfaced with a different brick or rock orientation. The stone texture may be duplicated from a variety of different styles of natural rock while still maintaining the overall shape of the block.

The mold may also have a series of intersecting, crossed ridges, orribs66 projecting inwardly from a common support surface or mat, which is secured to the inner front wall surface of the mold. The ridges are of sufficient rigidity to resist bending when the concrete is poured into the mold so as to form joints or spacing between the individual bricks or rocks very much similar in appearance to bricks or stones and mortar, and the thickness and depth of each ridge may be varied as illustrated. In addition, the wet cast machine allows use of multiple colors of concrete to produce a realistic looking natural stone color. A base color with an accent color can be utilized to provide the naturally variegated look of real stone.

Once the molds are placed in the production board, the production board B is then advanced through the filling apparatus for the type of concrete placement equipment that is used to fill the mold with concrete. A preferred approach is to fill the mold in the mold cavity by pouring wetcast concrete into the mold cavity. The SlabFlex® machine permits use of two or more colors of concrete to produce a realistic looking natural stone color, and the entire matrix of the concrete is colored concrete. A base color with an accent color may be used to provide the naturally variegated look of real stone or basic gray concrete without color may be used. The production board B is then run through various vibration cycles to densify and level the concrete in the rubber mold followed by smoothing the top surface by use of a hand cement finishing tool and placing the production board B and molds full of concrete in a suitable curing area during the hardening phase which is normally in the range of 12-20 hours depending upon the type of concrete mixture used and the size of the mold.

After curing, each concrete block is removed from the mold and typically is done by hand or using a vacuum demolding device, as shown inFIGS.8 and9. This is done by removing the mold and concrete block from theframe46 using the vacuum, followed by using a manual process and removing the remainder of the concrete block. The mold may be peeled off of the textured wall of the mold along thekeyways62 or hinged portions of the mold as shown inFIGS.8 and9. In this way, thetextured wall56 may be manually peeled away from the textured face to preserve the three-dimensional configuration of the textured wall. In other words, thekeyways62 permit hinging of the rubber mold to facilitate removal of the hardened concrete. The rubber molds incorporate a reinforced mesh fabric orstrap64 embedded within the rubber so as to provide reinforcement to thekeyways62 and to prevent tearing at the bottom of the mold. Reversing the mold and allowing the block to be pulled out using gravity is another form of removal. The mold is then placed back into theframes46 on the production board B.

In the removal process it will be appreciated that the trapezoidal or downwardly tapered configuration of the sidewalls and rear walls greatly facilitate removal of each block along with the formation ofvoids22 and24, particularly the void orcavity22 in the rear wall surface. In addition, the tapering of thesidewalls17 and18 rearwardly away from thefront wall12 enables much greater latitude in the formation of each wall into linear, curved, square or rectangular shapes.

FIGS.10 and11 are directed to a modified form ofmold70, which conforms in all respects to themold50 and like parts are correspondingly enumerated to the mold illustrated inFIG.7. The major departure is in the formation of a textured surface at oneend54′ and the location ofkeyways72 at opposite ends of thefront wall52′ opposite to the textured surface in thefront wall55. Anadditional keyway74 is formed in theopposite end wall53′ to thetextured end surface54′. In this way, upon completion of the casting process curing of the concrete block within the mold, bothwalls52′ and53′ may be peeled away from therear wall surface14′ and the end wall opposite to thetextured wall surface54′. Theblock10′ is illustrated inFIG.11 and comprises a fronttextured wall surface12′ and arear wall surface14′ which is tapered downwardly from tophorizontal surface16′. Similarly,opposite sidewall17′ tapers downwardly from thetop surface16′, and along with the front, rear sidewall surfaces12′,14′ and18′ terminate in the bottomhorizontal surface20′ which is parallel to thetop surface16′. Therear surface14′ is formed with a cavity (not shown) and the bottom surface is formed with a cavity that extends a partial length of thebottom surface20′ due to the presence of thesidewall18′.

Although preferred and modified forms or embodiments are herein set forth and described, the above and other modifications and changes may be made as well as their intended application for uses other than retaining walls without departing from the spirit and scope.

Claims (23)

We claim:

1. A masonry block, comprising:

a top surface;

a bottom surface having a first cavity extending upwardly from the bottom surface, the bottom surface including a front outer perimeter edge that is larger than a rear outer perimeter edge, the bottom surface surrounds the first cavity on two sides;

a rear surface tapered downwardly from the top surface to the bottom surface, the rear surface including a second cavity;

at least one textured external wall surface simulating the appearance of stone or brick, the textured external wall surface oriented vertically when the top surface and the bottom surface are oriented horizontally; and

wherein the second cavity has a maximum depth at a top end of the second cavity that is nearest to a top surface of the masonry block and a minimum depth that is smaller than the maximum depth.

2. The masonry block ofclaim 1, wherein the first cavity has angled walls that extend inwardly towards one another.

3. The masonry block ofclaim 2, wherein the angled walls form an inverted generally V-shaped configuration.

4. The masonry block ofclaim 2, wherein the angled walls are oriented at non-equal angles with respect to the bottom surface.

5. The masonry block ofclaim 1, wherein the minimum depth is at a bottom end of the second cavity that is nearest to a bottom surface of the masonry block.

6. The masonry block ofclaim 5, wherein the textured external wall surface is a front surface.

7. The masonry block ofclaim 6, wherein the textured external wall surface is 16 inches wide.

8. The masonry block ofclaim 5, wherein the second cavity includes a vertical wall that is perpendicular to the top surface.

9. The masonry block ofclaim 8, wherein the vertical wall of the second cavity is surrounded by the rear surface on at least two sides.

10. The masonry block ofclaim 1, wherein end walls taper inwardly from the textured external wall surface to the rear surface, such that a width of the textured external wall surface is larger than a width of the rear surface.

11. The masonry block ofclaim 1, wherein the bottom surface includes a front portion and a rear portion, the front portion of the bottom surface entirely separated from the rear portion of the bottom surface by the first cavity, the front portion coplanar with the rear portion.

12. A masonry block, comprising:

a top surface;

a rear surface tapered downwardly from the top surface to a flat bottom surface, the rear surface including a cavity that has a maximum depth at a top end of the cavity that is nearest to the top surface and a minimum depth that is smaller than the maximum depth; and at least one textured external wall surface simulating the appearance of stone or brick, the textured external wall surface oriented vertically when the top surface and the bottom surface are oriented horizontally.

13. The masonry block ofclaim 12, wherein the bottom surface has a recessed portion extending upwardly from the bottom surface, the bottom surface including a front outer perimeter edge that is larger than a rear outer perimeter edge, the bottom surface surrounds the recessed portion on two sides.

14. The masonry block ofclaim 13, wherein the recessed portion has angled walls that extend inwardly towards one another.

15. The masonry block ofclaim 14, wherein the angled walls form an inverted generally V-shaped configuration.

16. The masonry block ofclaim 14, wherein the angled walls are oriented at non-equal angles with respect to the bottom surface.

17. The masonry block ofclaim 13, wherein the minimum depth at a bottom end of the cavity is nearest to the bottom surface.

18. The masonry block ofclaim 13, wherein the textured external wall surface is a front surface.

19. The masonry block ofclaim 18, wherein a distance between the front surface to the rear surface is between 8 inches and 9 inches.

20. The masonry block ofclaim 13, wherein the textured external wall surface is 16 inches wide.

21. The masonry block ofclaim 13, wherein end walls taper inwardly from the textured external wall surface to the rear surface, such that a width of the textured external wall surface is larger than a width of the rear surface.

22. The masonry block ofclaim 13, wherein the bottom surface includes a front portion and a rear portion, the front portion of the bottom surface entirely separated from the rear portion of the bottom surface by the recessed portion, the front portion coplanar with the rear portion.

23. The masonry block ofclaim 12, the cavity includes a vertical wall that is parallel to the textured external wall surface.

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